arch/powerpc/include/asm/nohash/32/pgalloc.h

   1 #ifndef _ASM_POWERPC_PGALLOC_32_H
   2 #define _ASM_POWERPC_PGALLOC_32_H
   3
   4 #include <linux/threads.h>
   5 #include <linux/slab.h>
   6
   7 /*
   8  * Functions that deal with pagetables that could be at any level of
   9  * the table need to be passed an "index_size" so they know how to
  10  * handle allocation.  For PTE pages (which are linked to a struct
  11  * page for now, and drawn from the main get_free_pages() pool), the
  12  * allocation size will be (2^index_size * sizeof(pointer)) and
  13  * allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
  14  *
  15  * The maximum index size needs to be big enough to allow any
  16  * pagetable sizes we need, but small enough to fit in the low bits of
  17  * any page table pointer.  In other words all pagetables, even tiny
  18  * ones, must be aligned to allow at least enough low 0 bits to
  19  * contain this value.  This value is also used as a mask, so it must
  20  * be one less than a power of two.
  21  */
  22 #define MAX_PGTABLE_INDEX_SIZE  0xf
  23
  24 extern void __bad_pte(pmd_t *pmd);
  25
  26 extern struct kmem_cache *pgtable_cache[];
  27 #define PGT_CACHE(shift) ({                             \
  28                         BUG_ON(!(shift));               \
  29                         pgtable_cache[(shift) - 1];     \
  30                 })
  31
  32 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  33 {
  34         return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), GFP_KERNEL);
  35 }
  36
  37 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  38 {
  39         kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
  40 }
  41
  42 /*
  43  * We don't have any real pmd's, and this code never triggers because
  44  * the pgd will always be present..
  45  */
  46 /* #define pmd_alloc_one(mm,address)       ({ BUG(); ((pmd_t *)2); }) */
  47 #define pmd_free(mm, x)                 do { } while (0)
  48 #define __pmd_free_tlb(tlb,x,a)         do { } while (0)
  49 /* #define pgd_populate(mm, pmd, pte)      BUG() */
  50
  51 #ifndef CONFIG_BOOKE
  52
  53 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  54                                        pte_t *pte)
  55 {
  56         *pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
  57 }
  58
  59 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  60                                 pgtable_t pte_page)
  61 {
  62         *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_PRESENT);
  63 }
  64
  65 #define pmd_pgtable(pmd) pmd_page(pmd)
  66 #else
  67
  68 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  69                                        pte_t *pte)
  70 {
  71         *pmdp = __pmd((unsigned long)pte | _PMD_PRESENT);
  72 }
  73
  74 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  75                                 pgtable_t pte_page)
  76 {
  77         *pmdp = __pmd((unsigned long)lowmem_page_address(pte_page) | _PMD_PRESENT);
  78 }
  79
  80 #define pmd_pgtable(pmd) pmd_page(pmd)
  81 #endif
  82
  83 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
  84 extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
  85
  86 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  87 {
  88         free_page((unsigned long)pte);
  89 }
  90
  91 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
  92 {
  93         pgtable_page_dtor(ptepage);
  94         __free_page(ptepage);
  95 }
  96
  97 static inline void pgtable_free(void *table, unsigned index_size)
  98 {
  99         if (!index_size) {
 100                 free_page((unsigned long)table);
 101         } else {
 102                 BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
 103                 kmem_cache_free(PGT_CACHE(index_size), table);
 104         }
 105 }
 106
 107 #define check_pgt_cache()       do { } while (0)
 108
 109 #ifdef CONFIG_SMP
 110 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 111                                     void *table, int shift)
 112 {
 113         unsigned long pgf = (unsigned long)table;
 114         BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
 115         pgf |= shift;
 116         tlb_remove_table(tlb, (void *)pgf);
 117 }
 118
 119 static inline void __tlb_remove_table(void *_table)
 120 {
 121         void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
 122         unsigned shift = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
 123
 124         pgtable_free(table, shift);
 125 }
 126 #else
 127 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 128                                     void *table, int shift)
 129 {
 130         pgtable_free(table, shift);
 131 }
 132 #endif
 133
 134 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
 135                                   unsigned long address)
 136 {
 137         tlb_flush_pgtable(tlb, address);
 138         pgtable_page_dtor(table);
 139         pgtable_free_tlb(tlb, page_address(table), 0);
 140 }
 141 #endif /* _ASM_POWERPC_PGALLOC_32_H */